chore(context): refactor for consistency, optimize formatting, and simplify logic

- Cleaned up unnecessary comments in `__all__` definitions for better readability.
- Adjusted indentation and formatting across modules for improved clarity (e.g., long lines, logical grouping).
- Simplified conditional expressions and inline comments for context scoring and ranking.
- Replaced some hard-coded values with type-safe annotations (e.g., `ClassVar`).
- Removed unused imports and ensured consistent usage across test files.
- Updated `test_score_not_cached_on_context` to clarify caching behavior.
- Improved truncation strategy logic and marker handling.

backend/app/services/context/cache/context_cache.py

@@ -116,12 +116,16 @@ class ContextCache:
         # This avoids JSON serializing potentially large content strings
         context_data = []
         for ctx in contexts:
-            context_data.append({
-                "type": ctx.get_type().value,
-                "content_hash": self._hash_content(ctx.content),  # Hash instead of full content
-                "source": ctx.source,
-                "priority": ctx.priority,  # Already an int
-            })
+            context_data.append(
+                {
+                    "type": ctx.get_type().value,
+                    "content_hash": self._hash_content(
+                        ctx.content
+                    ),  # Hash instead of full content
+                    "source": ctx.source,
+                    "priority": ctx.priority,  # Already an int
+                }
+            )
 
         data = {
             "contexts": context_data,
@@ -412,7 +416,7 @@ class ContextCache:
                 # Get Redis info
                 info = await self._redis.info("memory")  # type: ignore
                 stats["redis_memory_used"] = info.get("used_memory_human", "unknown")
-            except Exception:
-                pass
+            except Exception as e:
+                logger.debug(f"Failed to get Redis stats: {e}")
 
         return stats